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View Full Version : 120mm Vantec Fans in canopy.. questions


mario8402
09/04/2007, 10:40 PM
I have 2 x 3" coralife fans in my canopy running off of a radio shack power brick (the front says "3-12v 800mA") and it has the adjustable slide that adjusts the volts etc....
they run the fans fine,but I am upgrading my lighting so I need some more flow.

I just picked up 2 vantec 120mm and was planning on using this power brick.. I plugged one in and it spins fine, but seems like it should be spinning alot faster. Then I put the other one in series and they both slow down... what kind of power do these things need and is this radio shack thing enough? what do I need?? I know I have read that people are running these fans so any advice you can provide will be great..

Need help asap, as I need to put these lights in even asap'r

Thanks
-mario

shelburn61
09/04/2007, 10:53 PM
The front of the fan says "12v 800mA"?

Your fans slowed down because the added fans were drawing more amperage than the dc converter (power brick) could handle.

.8 amps = 800mA. To run all the fans at full speed, you need a dc adapter(s) rated to handle the amperage required by all your fans. no problem running the fans at lower speed and they will be quieter also...

mario8402
09/04/2007, 11:01 PM
No, on the fan itself it says "12v dc .08 amps"

ok, so I just went and looked and noticed that its an AC adapter.. problem number one I supposed lol duh
This is the one that says "12v 800mA" on the front of it

These fans are already pretty quiet so, I am assuming at full speed, they still wont be as noisy as the coralife ones..

I guess I just need to find the right converter, but I am having a hard time finding one online. I am not too good with this watts/amps stuff

-mario

AZDesertRat
09/04/2007, 11:15 PM
If they are Vantec Stealths they run slower than other fans which is why they are rated at 28 dBa and 53 CFM. When you wire the fans up do not daisy chain or run the fans in series. Always wire them so each fans wiring goes back to the power supply not from fan to fan. When you do it the other way it cuts the voltage in half every time you add another fan. 800 mA is plenty, I run three Stealths on a 500mA adapter full speed.

shelburn61
09/04/2007, 11:18 PM
I've just cut converters off old electrical stuff...

BeanAnimal
09/05/2007, 06:35 AM
The fans are slowing down because you put them in series.

You need to run the fans in paralell. Add up the current rating of ALL of the fans and then find a power supply that is about 30% larger.

It it helps you can post the ratings of ALL of your fans :)

mario8402
09/05/2007, 07:40 AM
Thanks for everyones help so far!

ok, the fans that are currently in there are

coralife fans :
3.125"
31 CFM @ 31 dB

but these fans are coming out because they are smaller and they are way noisier.. I am not currently having a problem with the power supply running these 2


Vantec fans:
120mm
53CFM @ 28 dBA
http://images10.newegg.com/NeweggImage/productimage/11-999-614-05.jpg



does anyone have a diagram of how these need to be wired? a rough sketch would suffice lol

mario8402
09/05/2007, 12:57 PM
no one else has any suggestions?

BeanAnimal
09/05/2007, 01:47 PM
You need to post the power ratings from the lablels of ALL of the fans you intend to use.

mario8402
09/06/2007, 08:50 AM
I am only going to be using 4 vantec stealths

einsteins
09/06/2007, 09:05 AM
I went granger and got some AC 120mm fans for my hood and they rock!!
Just plug em in no DC adapters to deal with

ein

AZDesertRat
09/06/2007, 12:29 PM
AC fans are almost always much louder. You also cannot easily vary the speed like you can very easily with DC fans.